"Bad things will always happen" is a despicable shrug mentality. Bad things happen when people don't have their acts together in design, engineering, manufacturing, maintenance, and operation. The failure rates should be striving for zero, unlike the stunts Boeing has pulled on 737NG, MAX, and the 787.
Totally agree with you on the recent laxness in design and the regulatory capture that allowed it. But treating zero as a feasible goal is unrealistic. I've done code inspections for safety of flight code and making sure you have 100% coverage and branch coverage not just in the high level code but in assembler still doesn't get everything. You try to make sure that redundancy saves you (seriously boeing!) But common mode errors and just human fallibility to see all the possibilities mean we miss stuff. And all this is so much easier in software than in mechanical designs where redundancy sometimes just isn't doable. We shouldn't give up best practices, but we shouldn't have unreasonable expectations of them either. And not every engineering failure implies a failure in engineering process.
I wanted to clarify my last statement. Even when best practices are followed bad stuff happens, and that doesn't necessarily mean best practices need to change.
Of course not. Make improvements rather than knowingly shove-in bad Ducommun parts on the line or crappy MCAS. Also, hold manufacturers responsible when they take cost-shortcuts, sacrifice safety, and kill people. Boeing routinely gets a slap for doing so since it's also considered a strategic defense contractor, part of the MIC that greases palms in DC.
